1. Field of the Invention
This invention relates to an apparatus for scoring fracturable material, e.g., glass, and more particularly to a self-aligning scoring wheel.
2. Description of the Prior Art
There are various types of apparatuses for scoring fracturable material, e.g., glass, known in the prior art. In general, the scoring apparatuses include a scoring wheel rotatably mounted on a stem. The stem is mounted in a cylinder for vertical and rotational movement. A force is applied to the scoring wheel by way of the stem to urge the wheel against the glass to score same.
The stem is freely rotatable in the cylinder to align the rotating axis of the scoring wheel in a plane normal and transverse to the score path. The alignment of the score wheel is by the glass as it moves relative to the scoring wheel. In this manner, chipping of the glass is prevented as the score is imposed in the glass sheet. If the glass is chipped along the score line, the cut edge of the glass is damaged.
This damage reduces the edge strength of the cut edge and is normally removed by grinding or seaming to increase the edge strength.
A drawback of the prior art devices is that the stem tends to tilt in the cylinder thereby reducing the rotational motion of the stem.
It would be advantageous, therefore, if a scoring apparatus was available that did not have the limitations of the prior art.